Most canopy returns are not quality problems. They are fitment problems — someone ordered a 5.5 ft cap for a 6.5 ft bed, or bought a cap built for the previous generation of a truck that looked the same.
You need three numbers before you order: bed length, model year, and what is already bolted to the bed rails. This truck cap fitment chart covers the pickups we build for, with the bed lengths and year ranges we publish on each product page.
The 3 numbers to check first
- Bed length — measured inside the bed, from the bulkhead to the inside face of the closed tailgate. Not the wheelbase, not the cab size.
- Model year — not the generation nickname. Bed dimensions usually hold within a generation and change across one.
- What is on the rails — a drop-in bed liner, a spray-in liner, an OEM rail cap, or a retractable tonneau track all change the clamping surface.
If you are not certain of the first one, measure it. Our truck bed measuring guide walks through it in four steps, and the full bed dimensions chart lists the numbers by model.
Truck cap fitment chart
Bed lengths below are the configurations Armacap builds for. Year range is the fitment published on that product page. Prices are current factory-direct sale prices in USD.
| Truck | Bed lengths | Fitment years | From |
|---|---|---|---|
| Ford F-150 | 5.5 ft / 6.5 ft | 2015–2026 (5.5 ft) | $2,142 |
| Chevrolet Silverado 1500 | 5.8 ft / 6.6 ft | 2019–2026 (5.8 ft) | $2,142 |
| GMC Sierra 1500 | 5.8 ft / 6.6 ft | 2019–2026 (5.8 ft) | $2,142 |
| RAM 1500 | 5.7 ft / 6.4 ft | 2019–2026 (5.7 ft) | $2,142 |
| RAM 2500 / 3500 | 6.4 ft | see product page | — |
| Toyota Tacoma | 5.0 ft / 6.0 ft | 2016–2026 (5.0 ft) | $1,962 |
| Toyota Tundra | 5.5 ft / 6.5 ft | 2014–2026 (5.5 ft) | $2,142 |
| Chevrolet Colorado | 5.2 ft / 6.2 ft | 2015–2026 (5.2 ft) | $1,962 |
| GMC Canyon | 5.2 ft / 6.2 ft | see product page | — |
| Jeep Gladiator | 5.0 ft | 2020–2026 | $1,962 |
| Ford Ranger | 5.0 ft / 6.0 ft | see product page | — |
| Nissan Frontier | 5.0 ft / 6.1 ft | see product page | — |
| Nissan Titan | 5.5 ft / 6.5 ft | see product page | — |
| Honda Ridgeline | 5.3 ft | see product page | — |
Year breaks that catch people out
A canopy that fits a 2020 truck does not automatically fit the 2021 of the same nameplate. When a model changes generation, the bed rails, the tailgate profile and the cab-to-bed gap can all move even when the advertised bed length stays the same.
The model years where we get the most fitment questions:
- Ford F-150 — the cab and bed changed for 2021. Orders for 2021 and newer should confirm against the current fitment note.
- Chevrolet Silverado 1500 and GMC Sierra 1500 — the current body started in 2019, which is where our published range begins.
- RAM 1500 — the current generation also starts at 2019.
- Toyota Tacoma — the third generation ran from 2016; a newer generation followed, so 2024 and later trucks need checking.
- Toyota Tundra — a redesign arrived for 2022 within our published range.
- Chevrolet Colorado and GMC Canyon — a new generation arrived for 2023.
- Jeep Gladiator — launched in 2020, one bed length only.
If your model year sits at the start or the end of any published range, send a photo of the bed rails before ordering. It takes a minute and it removes the guesswork. Model-specific detail is also covered in our F-150 bed cap guide, Silverado topper guide, RAM 1500 canopy guide and Tacoma truck cap guide.
How to measure your bed in four steps
- Close the tailgate.
- Measure from the inside face of the bulkhead, at the front of the bed, to the inside face of the tailgate.
- Measure at bed floor level, not over the rail tops.
- Write down the number in inches, then round to the nearest published length.
Do not measure from the outside of the tailgate, and do not trust a number printed on a window sticker — those are nominal sizes, and the real opening is often an inch or two off the round number. The full routine is in our measuring guide.
Once you have the measured figure, match it to the nearest published configuration in the truck cap fitment chart above. If your number lands between two, send it to us with the model year before ordering rather than rounding up.
Cap, topper, canopy or camper shell — the same chart applies
The four words describe the same accessory in different regions and different decades, and the fitment rules do not change with the name. Whether you are shopping for a truck cap fitment chart entry, a camper shell or an aluminium canopy, the three numbers you need are identical: bed length, model year, and what is on the rails.
A tonneau cover is different. It mounts inside the bed rails and is measured across the rails, while a canopy clamps on top of them. That is why a cover that fits your truck tells you almost nothing about which canopy will — the two never share a fitment chart. We covered the distinction in canopy vs tonneau vs camper shell.
Five fitment mistakes worth avoiding
1. Guessing the bed from the cab
A crew cab does not tell you the bed. Most half-ton trucks offer two or three bed lengths with the same cab, and the short bed and the standard bed sit several inches apart.
2. Ignoring what is already on the rails
An existing drop-in liner adds thickness at the bulkhead and along the rails. A spray-in liner adds less but is not zero. A retractable tonneau cover leaves a track bolted to the rail that has to come off first.
3. Assuming the same nameplate means the same bed
A 2015 F-150 and a 2026 F-150 are different trucks. Even where the advertised bed length matches, the rail profile can differ enough to change clamp placement.
4. Ordering before the truck exists
If the truck is on order, wait until you have the build sheet with the bed length confirmed. Guessing here costs a return freight bill on a crate that weighs hundreds of pounds.
5. Forgetting the tailgate
Some tailgates are not flat across the top, and some carry a spoiler or a step that moves the sealing line at the back of the canopy. Check it before you order, not after.
What to record before you place a fleet or shop order
Fitment errors are the most expensive comeback a shop can take on a canopy: the unit is crated, the freight is real, and the customer's truck is already in the bay. Four fields on the order form remove most of the risk:
- Model year and trim — not just the nameplate. Trim packages change bed rail hardware.
- Bed length, measured — taken on the truck, not read off a sticker.
- Existing bed hardware — liner type, rail caps, any tonneau track still fitted.
- A photo of the rails — worth more than a paragraph of description when a truck sits at a generation boundary.
Keep one reference unit per bed length in the shop if you install regularly. Measuring a truck against a canopy you know is faster than re-measuring the truck, and it catches the generation-boundary cases before the crate is opened.
What fits with what you already have
- Factory bed liner, drop-in — usually fine. Clamps sit over the rail, but the liner lip can need trimming at the clamp points.
- Spray-in liner — fine. Thickness is small enough that clamps seat normally.
- OEM rail caps — usually fine, no drilling needed.
- Retractable or tri-fold tonneau — the track has to come off. Our canopies mount with no-drill clamps on the OEM bed rails, so removing a tonneau track does not leave holes.
- Bed rack or ladder rack — check clamp interference before ordering.
Keep this truck cap fitment chart handy when you quote. For shops and fleet buyers ordering more than one unit, our manufacturing overview covers lead times and ordering, and wholesale landed cost breaks down the freight math.
Browse truck canopies by bed length · Ford · Chevrolet · Toyota · RAM
FAQ
How do I know what size truck cap fits my truck?
You need three numbers: bed length measured inside from bulkhead to closed tailgate, model year, and what is fitted to the bed rails. Match those against the manufacturer's published fitment, not against a similar-looking truck.
Will a truck cap from one year fit another year of the same model?
Sometimes, but not reliably across a generation change. Bed rails, tailgate profile and cab-to-bed gaps can move even when the advertised bed length is unchanged. Check the published year range for the specific product.
What bed lengths does a Ford F-150 come in?
Armacap builds for the 5.5 ft and 6.5 ft beds. The published fitment for the 5.5 ft aluminum canopy is 2015–2026 — confirm the exact range on the product page for the bed length you have.
Do I need to remove my tonneau cover before fitting a canopy?
Yes, if it uses a bolted side track. Armacap canopies clamp to the OEM bed rails without drilling, so removing a tonneau track leaves no holes behind.
Can I fit a canopy over a drop-in bed liner?
Usually yes. The liner lip can need trimming where the clamps sit. Spray-in liners are thin enough that clamps seat normally without modification.
Do I need a different fitment chart for a camper shell or a topper?
No. Cap, topper, canopy and camper shell describe the same accessory, and the same truck cap fitment chart applies to all of them. Only a tonneau cover is measured differently, because it mounts inside the bed rails instead of on top.
What happens if I order the wrong bed length?
Measure before ordering rather than after. Crated canopies are heavy and return freight is expensive — a one-minute measurement on the truck avoids it.